Temik proving hard to replace in cotton, peanuts

• Farmers in the Southeast knew going into the 2011 spring planting season that Temik was being taken off the market — gradually up to 2016.
• They didn’t count on a lawsuit in West Virginia stopping production and significantly restricting the amount of Temik available for the 2011 cropping season.
• The fallout from shortages in Temik supply has already been significant in determining what crops farmers do and don’t plant.

Temik has been widely used in crops in the Southeast since the early 1980s, and though maligned by both farmers and environmental activists because of its safety liabilities, there is no doubt the product has contributed significantly to the growth in agricultural productivity around the world.

Farmers in the Southeast knew going into the 2011 spring planting season that Temik was being taken off the market — gradually up to 2016. They didn’t count on a lawsuit in West Virginia stopping production and significantly restricting the amount of Temik available for the 2011 cropping season.

The fallout from shortages in Temik supply has already been significant in determining what crops farmers do and don’t plant. However, having been on the market and so widely used for so many years, the use of old, lesser used, chemistry to replace Temik could have some far-reaching affects.

The toughest replacement questions are facing growers who have a cotton and peanut rotation.

Cotton acreage, for example, is expected to be up significantly in 2011. Temik at 5-8 pounds per acre, applied at planting, has been a standard for cotton growers for as long as most Southeast growers have been growing cotton.

The same is even truer for peanuts, another staple crop of the Southeast. Peanut farmers may have fewer options for Temik replacements than cotton growers.

Long-time Virginia Tech Plant Pathologist Pat Phipps says in some areas of the upper Southeast he recommends using existing Temik on peanuts rather than on cotton.

“Especially in Virginia and in some parts of North Carolina, peanut growers just don’t have many options, especially in fields with a history of high nematode populations and soil-borne diseases,” Phipps says.

North Carolina State Entomologist Jack Bachelor, who has studied the use of Temik for thrips control in cotton for many years, says the options for Temik alternatives are relatively few when it comes to managing both early season insects and nematodes.

“For thrips control and cotton yield, in our replicated tests, Temik 15G at the 5.0 product rate has been a little better from an economic standpoint than any one of the seed treatments (Gaucho Grade, Cruiser, Avicta Complete or Aeris) plus a foliar spray (typically acephate) at the first true leaf stage,” he says.

“According to our latest survey of independent consultants, last year Temik alone was used on 54 percent of the consulted acreage; an additional 17.5 percent of this acreage was planted to Temik (most often 5 pounds) plus a seed treatment.”

According to North Carolina State University Plant Pathologist, Steve Koenning, Aeris and Avicta Complete, which contain different nematicides (thiodicarb and abemectin) in addition to the thrips-active insecticide, are roughly equivalent to 4-5 pounds of Temik 15G for nematodes. For higher populations of nematodes, growers have routinely used 7 pounds of Temik per acre or inject the soil sterilant Telone II.

Acceleron seed treatment will be offered to cotton growers buying Deltapine seed in 2011. This seed coat should perform comparable to Aeris, Gaucho Grande or Avicta Complete for thrips control because Acceleron shares the same active ingredients and amounts used in Gaucho Grande (thrips only) and in their thrips plus nematode versions similar to Aeris (imidacloprid plus thiodicarb) and another similar to Avicta Complete (thiamethoxam plus abemectin).

Thimet labeled for cotton

Thimet 20 G, a granular insecticide is labeled for cotton. It is a granular, in-furrow insecticide and can be used similar to Temik for thrips control. A low rate (3.3 pounds per acre) is probably best for cotton planted after May 20. Most growers are past the optimum time for using the higher rate of 8.2 pounds per acre.

“With Temik and seed treatments dominating the market for the past decade or more Thimet and other phorate-containing insecticides have not been evaluated in North Carolina recently. If a producer elects to use one of these materials, we recommend trying it on limited acreage in 2011,” Bachelor says.

Bachelor says in past testing of this product, Thimet sometimes showed less residual control of thrips than Temik. This product may cause phytotoxicity, particularly under cool wet conditions and should not be used following diuron-containing herbicides such as Karmex and Direx.

Unlike Temik which has residual activity on both nematodes and thrips, Thimet does not control nematodes.

An in-furrow at-planting spray of one pound of active ingredient of acephate (Orthene and other generic brand names) also provides some control of thrips, although its effectiveness against high thrips levels may be marginal.

Although foliar sprays with materials such as acephate are taken up by cotton seedlings, even multiple applications often result in poor thrips control.

Peanuts are typically grown on lighter, sandier soils in the Southeast, which provides an ideal environment for root knot nematodes. These microscopic pests cause economic losses by damaging the developing root system, by forming galls on the pegs and weakening them at harvest, and by causing significant deformation of the pods.

Two alternatives are available to peanut growers with high levels of root knot nematodes. Neither has had extensive field testing, primarily because of the efficacy and relatively low cost of Temik.

NemOut is a biological product that produces spores of a fungus that parasitizes eggs of root knot nematodes. Limited testing in Georgia and Florida indicate .3 pound per acre applied in furrow at planting and another .3 pound per acre at pegging show some reduction in nematode populations and damage to peanuts.

Growers who try NemOut in 2011 should take care to ensure that the living spores in the product are kept alive and that living colonies are present at rates between 0.3 and 0.6 pound per acre for use both in-furrow and at pegging time.

Resistant peanut varieties not great option

Nematode resistant, even nematode-tolerant peanut varieties are not a great option for peanut growers seeking Temik options. Three varieties are available, though the first two COAN and NemaTam may be in short supply due to lack of demand over the past decade or so.

A more viable variety for runner type growers in the Southeast is Tiftguard. In addition to resistance to root knot nematodes, Tiftguard has resistance to tomato spotted wilt virus.

Since its release in 2008, tests in Georgia and Florida indicate this runner type variety grown in fields with either problem will produce higher yields than the more commonly used varieties, which are susceptible to nematodes or TSWV.

Thrips are a serious threat to peanuts in the Southeast for a couple of reasons. These tiny insects can cause serious crop stunting and yield loss from feeding on immature peanut plants.

Perhaps more damaging to peanuts is tomato spotted wilt virus, which is spread by thrips. TSWV is especially challenging for peanut growers because it occurs so sporadically. When occurring at high levels and on varieties that are highly susceptible to the disease, TSWV can cause devastating yield losses.

For a long, long time Temik has been the standard treatment for thrips control in peanuts. There is short list of replacements, primarily phorate-containing materials, primarily Thimet and Vydate, a carbamate that contains the active ingredient oxymil.

Phorates can be particularly challenging for growers who grow both peanuts and cotton. Thimet is one of several organo-phosphate materials linked to problems with diuron, and fluometuron herbicide use in cotton.

Growers should carefully check the label of any diuron-containing herbicide used in conjunction with a phorate-containing product.